IARC 60th Anniversary - 19-21 May 2026
Session : WCRFI Session - Capacity building in low and middle income countries in the field of diet, nutrition, physical activity for global cancer prevention
Early life factors and risk of acute leukemia in children
KINTOSSOU K. 1, BLANCO-LOPEZ J. 2, SHINY M. 2, IGUACEL I. 3, PISANU S. 4, ALMEIDA C. 5, STELIAROVA-FOUCHER E. 2, SIERENS C. 6, GUNTER M. 7, LADAS E. 8, BARR R. 9, VAN HERCK K. 6, KOZLAKIDIS Z. 2, HUYBRECHTS I. 2
1 Institut Pasteur de Côte d'Ivoire, Abidjan, Côte d'Ivoire; 2 International Agency for Research on Cancer, Lyon, France; 3 Faculty of Health Sciences, University of Zaragoza, Zaragoza, Spain; 4 Department of Biomedical Sciences, Section of Microbiology and Virology, University of Cagliari, Cagliari, Italy; 5 Department of Nutrition, Federal University of Paraná, Curitiba, Brazil; 6 Department of Public Health and Primary Care, Ghent University, Ghent, Belgium; 7 Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom; 8 Division of Hematology/Oncology/Stem Cell Transplantation, Department of Pediatrics, Columbia University Irving Medical Center, New York, United States; 9 Department of Pediatrics, Pathology and Medicine, McMaster University, Hamilton, Canada
Background
Acute leukemia is the most frequent cancer in children, yet its etiology remains largely unexplained. The early age at diagnosis and marked global variation in incidence suggest that exposures occurring during pregnancy, the perinatal period, and early childhood may play an essential role in disease development.
Objectives
To systematically assess and quantify the associations between early life factors including perinatal characteristics, maternal lifestyle during pregnancy, and early childhood nutrition and the risk of acute leukemia in children.
Methods
Three complementary systematic reviews and meta-analyses were conducted in accordance with PRISMA guidelines and registered in PROSPERO. Epidemiological studies published up to 2023–2024 were identified through PubMed and Web of Science without restrictions on language or publication year. Case–control studies, cohort studies, and pooled analyses evaluating early life exposures and childhood acute leukemia were included. Pooled effect estimates (odds ratios [ORs] or relative risks [RRs]) and 95% confidence intervals (CIs) were calculated using the Generic Inverse Variance method, with random-effects models applied where appropriate.
Results
The meta-analysis identified several factors associated with the risk of childhood leukemia. Maternal consumption of fruits (≥2 servings/day) and breastfeeding were protective against acute lymphoblastic leukemia (ALL), with ORs of 0.71(95% CI: 0.59–0.86) and 0.85 (95% CI: 0.76–0.94), respectively. In contrast, an increased risk of ALL was associated with high birth weight (>4000g; OR=1.20; 95% CI: 1.08-1.34), maternal history of abortion (OR=1.24; 95% CI: 1.08-1.43), maternal diabetes (OR=1.41; 95% CI: 1.23-1.60), maternal hypertension (OR=1.21; 95% CI: 1.06-1.38), cesarean delivery (OR=1.10; 95% CI: 1.05-1.16), and maternal coffee consumption exceeding two cups per day (OR= 1.45, 95%CI: 1.12–1.89).
Similar associations were observed for acute leukemia overall, with increased risks linked to high birth weight (OR=1.35; 95% CI: 1.20-1.53), maternal history of abortion (OR=1.27; 95% CI: 1.12-1.43), and maternal diabetes (OR=1.30; 95% CI: 1.14-1.48). Evidence regarding other early life dietary factors and neonatal vitamin K administration was inconclusive.
Conclusions / Implications
This integrated evidence indicates that early life factors play a meaningful role in the development of childhood acute leukemia. Although individual associations are modest, many identified factors are potentially modifiable or manageable through maternal and child health interventions. These findings support the development of prevention-oriented strategies and policies targeting early-life exposures to reduce the global burden of childhood leukemia.